Crowley’s (1976) study of Nganyaywana is used to illustrate certain points relevant to comparative Australian linguistics. In particular, reliance on shared innovations for subgrouping is more problematic than often supposed because even the unusual phonological development of Nganyaywana can be observed as independent parallel developments elsewhere, and because uncertainties in reconstruction can also impinge on this evidence for subgrouping. Meanwhile Crowley’s finding that Nganyaywana has borrowed little from its neighbours goes against claims that Australian languages borrow heavily from each other. This adds to the evidence that it is reasonable to supplement the traditional approach to subgrouping with the independent evidence of lexicostatistics.